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Newsgroups Explained
in Plain English
The General Concept
Every ISP has a “news server,” which is like a giant bulletin board. Imagine a bulletin board in the lobby of a
large office building to which anybody can pin a notice, picture, CD, or DVD, and anybody can come along and take
whatever interests them. Now imagine that instead of taking something down, you can push a button and get a perfect
copy.
The bulletin board is popular and there isn’t enough room to fit everything on it, so buttons were added to the
top – each one representing an interest group. There are buttons for art, music, cartoons, erotica, and every other
possible thing. You press a button, and the contents of the
bulletin board change to show things in that interest group.
Now imagine that the bulletin board in your building is connected to the bulletin boards in every other building
in the world. When you press the erotica button, pictures and videos from around the globe magically appear.
Now imagine that you don’t have to go down to the lobby to see what is on the bulletin board – that you can just
start up a browser program on your computer and see what’s there. Or even better, you can use a special browser
that will automatically retrieve things for you. For example, you would point such a program at the erotica
section, press the start button, and then watch as it rapidly downloads files. Perhaps you would let it run at night,
and then in the morning review the files it found.
The “News” Nickname
The term “news” here has nothing to do with the CNN kind of news, or with RSS news feeds. The global network of
newsgroup servers pre-dates the internet, and goes back to a time when the only things posted were small messages.
The original intent of Usenet, the technical name for this network, was to have a global bulletin board where
researchers could post, and discuss, “new” things they discovered, and thus, the nickname “news.”
The News Server
Just as a web server holds pages that you view with a browser, a news server holds “posts” that you view with a
news-browser. A post is a message that anybody can write and upload to the server, and it can contain an attached
file, just like an email message. Posts are organized into newsgroups. So, when you access a news server, you first
select a newsgroup, and then see what posts are in it. You can then download posts or upload posts.
Just like a web server, a news server has a URL. For example, our web server’s URL is:
www.techsono.com
Our news server’s URL is:
news.techsono-news.com
Newsgroups
On the news server are thousands of newsgroups for every conceivable topic. Newsgroup names are similar to web
page URL’s. Here are two examples:
alt.astronomy
alt.binaries.astronomy
There are two kinds of newsgroups: discussion groups and “binary” groups. “Binary” just means “file” in newsgroup
land. So, if you wanted to discuss astronomy, you would go to alt.astronomy and read what other people wrote there,
and maybe post something yourself. If you wanted to download files associated with astronomy, you would go into
alt.binaries.astronomy and see what files were available. You could also upload files.
Posts
A post consists of a header and body. The header is simply a few items such as the date, the email address of
the poster, and the subject. The body is the words and/or attached file. The format is almost exactly the same
as an email message. So, when you start up your email program, you see a list of your new messages, which is a
list of “headers.” You look at the headers, click on a message, and then you see the “body” – what the sender wrote.
The exact same thing happens in a newsgroup, except that the messages aren’t sent to you directly, but can be seen
by anybody.
A post looks like this:
From: "Some Guy"
Subject: New Planet Discovered
Newsgroups: alt.astronomy
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
The first three lines are the headers. The blah-blah-blah’s are the body. There will also be a few more headers,
but you don’t need to worry about them.
Binary Posts
When somebody emails you a file, it is called an “attachment.” In reality, nothing is “attached.” The attached
file is actually converted into text and put into the message along with the headers and the body. Everything is
included in one file. It is your email program that creates the illusion of an attachment. The same is true with
binary posts. Here is what one looks like:
From: "Some Guy"
Subject: Picture of New Planet – new_planet.jpg (123kb)
Newsgroups: alt.binaries.astronomy
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
Blah, blah, blah. Blah, blah, blah. Blah, blah, blah.
=ybegin part=11 line=128 size=123000 name=picture.jpg
dkfjakdjfkaa98f0adfuadfuadf89dfa0fdufua0fdjfajdf
fa0d98fa0di1fadfa-d8fadjfa-fd0fua-fujadfja-fdf-adq
aogjoagjaja0-g-wjekjajfw’letj0ojgpadgpagjapgdjgg
etc.
=yend size=123000 part=1 pcrc32=9fe0e51a
Notice that the binary post is exactly the same as a text post except for the gibberish at the bottom – that is
what a picture looks like when it is encoded into text. You don’t need to worry about it too much because, just like
your email program, your news-reader program will automatically convert it back into a picture file.
Large Binary Posts
Just like email, you can’t attach large files to a post. Newsgroups have size limits just like email boxes.
The limit is not set in stone, but things work better when posts are kept under a megabyte. So, large files are
broken up into a series of posts. A large picture might be posted in four parts, an MP3 in ten parts, and a DVD in
thousands of parts. You can download each part and then paste the posts together to re-create the file, but for
large files that would quickly lead to insanity and the job is best left to a news-reader program.
Continue on with Advanced Topics or
Newsgroup Software.
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